I have less than 2,000 miles on my pickup and took it in and they said it's the leaf spring. They retort the leaf spring and put additional grease on it less than 250 miles later the rattle is back. They said to bring it in and they will add more lubricant which I replied I did not pay $40,000 to come in ever 250 miles for y'all to add more lubricant to it fix the damn thing